One day Professor Rosenberg was giving a big test to his students. He handed out all of the tests and went back to his desk to wait. Once the test was over, the students all handed the tests back in.
Professor Rosenberg noticed that one of the students had attached a $100 bill to his test with a note saying "A dollar per point." The next class Professor Rosenberg handed the tests back out.
This student got back his test and $64 change.